hlc: Calculating the bilateral harmonic log-change (HLC) price...

In PriceIndices: Calculating Bilateral and Multilateral Price Indexes

Calculating the bilateral harmonic log-change (HLC) price index

Description

This function returns a value (or vector of values) of the bilateral harmonic log-change price index.

Usage

hlc(data, start, end, interval = FALSE)

Arguments

data	The user's data frame with information about sold products. It must contain columns: time (as Date in format: year-month-day,e.g. '2020-12-01'), prices (as positive numeric), quantities (as positive numeric) and prodID (as numeric, factor or character).
start	The base period (as character) limited to the year and month, e.g. "2020-03".
end	The research period (as character) limited to the year and month, e.g. "2020-04".
interval	A logical value indicating whether the function is to compare the research period defined by end to the base period defined by start (then interval is set to FALSE) or all fixed base indices are to be calculated. In this latter case, all months from the time interval <start,end> are considered and start defines the base period (interval is set to TRUE).

Value

The function returns a value (or vector of values) of the bilateral harmonic log-change price index (HLC), i.e., the log-change index constructed using weights equal to the harmonic mean of expenditure shares (rather than the arithmetic mean used in the Törnqvist index). If the interval parameter is set to TRUE, the function returns a vector of price index values without dates. To get information about both price index values and corresponding dates, please see functions: price_indices or final_index. The function does not take into account aggregating over outlets or product subgroups (to consider these types of aggregating, please use the final_index function).

Examples

hlc(sugar, start="2018-12", end="2019-12")
hlc(milk, start="2018-12", end="2020-01", interval=TRUE)

PriceIndices documentation built on Feb. 26, 2026, 1:07 a.m.